AET. 18 MINERALS OF ITALIAN MOUNTAIN CROSS AND SHANNON 3 



dominant feldspathic constituent between granite and quartz diorit© 

 for which I have long used the term quartz monzonite. The " gran- 

 ite " of South Italian Mountain probably has nearly as much plagio- 

 clase as the '' diorite," though orthoclase is the more conspicuous in 

 the former rock. 



Pre-Cambrian Paleozoic 



formations 



Mesozoic 

 formations 



Intrusive Faults 



Fig. 1. — Geologic Map of Vicinity of Itall\n Mountain 



The Paleozoic bed lying between the intrusive masses and the pre- 

 Cambrian complex are not only highly metamorphosed but are folded 

 and faulted in most intricate manners. On the folio structure sec- 

 tion sheet of the Crested Butte quadrangle Mr. Eldridge has indi- 

 cated by symbols a great variety of dips, both anticlinal and syn- 



